The Environmental Protection Agency of the Federal Government and similar regulatory agencies of the States require capture or recycle of hydrocarbon vapors created during the filling of gasoline storage tanks at a gasoline service station. These regulations also require that vapors be recovered from the gasoline tanks of automobiles during fill-ups.
U.S. Pat. No. 3,915,205 to Wagner (the disclosure of which is herein incorporated by reference) discloses a vapor recovery system for recovering hydrocarbon vapors from storage tanks and from automobiles during fill-ups. The system illustrated in FIG. 3 includes a manifold 126 wherein vent lines from a plurality of hydrocarbon storage tanks are directed. Also in communication with the manifold 126 is a vent line 130 for venting vapors to the atmosphere and a vapor recovery line 131. Because of the proximity of vent line 130 to the vent lines of the storage tanks vapors are just as likely to escape to the atmosphere through vent line 130 as vapors are likely to travel up vapor recovery line 131. The presence of only a single vent line to the atmosphere is disturbing because if this vent line is ever plugged by debris or destroyed by accident the hydrocarbon storage tanks will not vent during regular operation of the service station. Clogging or plugging of the vent line 130, in addition to being illegal, creates a hazardous situation.
The present invention overcomes these disadvantages of the prior art.